Ultrasonic diagnostic apparatuses have been conventionally used in medical care today in examining or diagnosing various types of body tissues such as those of a heart, a liver, a kidney, and a mammary gland. Ultrasonic diagnostic apparatuses has advantages over other medical image diagnostic apparatuses, such as X-ray diagnostic apparatuses and X-ray computed tomographic imaging apparatuses, in that they are easier to use and non-intrusive to subjects without the risk of radiation exposure, for example.
Such an ultrasonic diagnostic apparatus generates and displays a tomographic image (B-mode image) of a tissue structure in a subject by transmitting ultrasound waves from an ultrasound probe, and receiving reflection wave signals reflected on the internal tissues of the subject. A more recent ultrasonic diagnostic apparatus generates and displays a color Doppler image presenting blood flow information such as the velocity, turbulence, and power of blood flows in a distinguishable manner by colors, by taking advantage of the Doppler shift of ultrasonic waves, as well as a region where the blood flows are present within a subject. There have been situations where visibility of an image captured by such an ultrasonic diagnostic apparatus is degraded.